condition mean min max ZT0-3 3380.831975 3380.831975 3380.831975 ZT4-7 2734.2309800000003 2734.2309800000003 2734.2309800000003 ZT8-11 2028.4987409999999 2028.4987409999999 2028.4987409999999 ZT12-15 2285.432754 2285.432754 2285.432754 ZT16-19 1959.970247 1959.970247 1959.970247 ZT20-23 1282.573545 1282.573545 1282.573545